Preparation Of Graphene And Cb[n]-based Electrochemical Sensing Platform And The Application For Glucose Sensing

The electrochemical biosensors based on graphene has attracted tremendous scientific and technological attention because of its large specific surface area and great electron mobility as a kind of two-dimension material.CB[n]are a new group of macrocyclic compounds with polar carbonyl groups surrounding the portals and pumpkin-shaped molecules.It's expected that preparation of electrochemical biosensors based on graphene and CB[n]will improve the selectivity and application of the according electrochemical sensor because of the host-guest recognition.In this article,we constructed a GCE modified by Nafion dispersed electrochemical reduced graphene oxide?Nafion-ERGO?and AuNPs firstly.Besides,the properties of detecting H₂O₂ was researched.Secondly,CB[n]was modified the GCE/ERGO-Nafion/AuNPs electrode through immersing to prepare a electrochemical biosensors platform.In addition,some kind of molecules was detected by this platform.Finally,Fc-COOH,the electron mediators,and GOD modify the platform to construct a Glu biosensor.The parameter of Glu biosensor was also researched.The main work includes the following:?1?Preparation of GCE/ERGO-Nafion/AuNPs electrode.The GO-Nafion nano-composites were first assembled on GCE surface to produce GO-nafion electrode.Then GO were electrochemically reduced.Afterwards,AuNPs were electrodeposited on the modified GCE and formed GCE/ERGO-Nifion/AuNPs electrode.The ERGO-Nafion nanocomposites and the electrodeposited AuNPs were characterized by Raman spectroscopy,atomic force microscope,infrared spectroscopy and scanning electron microscopy.The results showed that the thickness of GO were 1.3nm and GO were reduced successfully and the AuNPs were uniformly dispersed on the GCE/ERGO-Naf-ion electrode with size of about 50nm.The cyclic voltammagrams,EIS and amperomet-ric method were used to evaluate electrocatalytic properties of the GCE/ERGO-Nafion/Nafion electrode.The results showed that the modified electrode displayed good electrocatalytic activity to the reduction of hydrogen peroxide with a detection limit of2?M hydrogen peroxide based on a signal-to-noise ratio of 3?S/N=3?.The sensor has great sensitivity?574.8?A/?mM·cm²??,wide linear range?0.02-23 mM?,good selectivity,reproducibility,and long-term stability.?2?Construction of GCE/ERGO-Nafion/AuNPs/CB[n]platform.The mesoporous aforementioned GCE/ERGO-Nafion/AuNPs electrode was immersed into CB[7]solution for 12h.The platform was characterized by Raman spectroscopy,atomic force microscope,infrared spectroscopy and scanning electron microscopy.The results showed that CB[7]self-assembled on the surface of graphene/Au modified electrode through the interaction between the carbonyl groups of CB[7]with AuNPs.Fe?CN?₆^3-/4-,amino acid with phenyl ring,hydroxybenzyl alcohol,Fc and its derivatives serve as the substrates,and the electrochemical properties with the response of cyclic voltammetry of GCE/ERGO-Nafion/AuNPs/CB[7]electrode have been evaluated.The results showed that the platform can detect some target molecules of them.?3?Preparation of GCE/ERGO-Nafion/AuNPs/CB[7]/Fc-COOH/GOD electro-chemical biosensor.The aforementioned GCE/ERGO-Nafion/AuNPs/CB[7]platform was immersed into Fc-COOH solution for 12h and then immersed into 5mg/ml GOD solution for 12h.The electrochemical biosensor was characterized by infrared spectroscopy,cyclic voltammetry and EIS.The results showed that the Glu electroche-mical sensor has a sensitivity of 3.8?A/mM and wide linear range?0.2mM-1mM?.